If you do not want to pay for the security wares, there are a lot free wares just like AVG Antivirus,Avast and Avira which are think the best free Antivirus Softwares, and now, you have another choice! The Microsoft Security Essentials.
If you want to download Microsoft Security Essentials, please read the post first.
This Microsoft Security Essentials beta is available only to customers in the United States, Israel, China and Brazil .I have download this free software for test, and it works well(I am using Kaspersky internet security 2009 on my computers)I tested it on Windows XP sp3 and was quite impressed with it.
Notice:In order to void problems, you should uninstall other anti-virus wares before you install this free security software if you have one.
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